A "game" somewhat similar to "Devil's Advocate." Unlike Devil's Advocate, Bastard's Advocate relies on a person being a complete dick and/or asshole to someone else, relentlessly giving them shit. The ultimate reward here is to get the poor bastard to cry because he is a cunt rag.
You're gay. You're an idiot. I hate you. Faggot. Haha isn't Bastard's Advocate fun?!